The effect of filament winding mosaic pattern on the stress state of filament wound composite flywheel disk

A filament wound spinning composite disk is characterised by the mosaic pattern configuration produced during the filament winding process. In this structure, each helically wound layer consists of curved triangular shaped units alternating in the radial and circumferential directions. Filament wound composite shells are usually analysed based on the implementation of mechanics of composite laminates. Usually, the mosaic pattern configuration is not considered in the general stress analysis procedures based on the conventional modelling of laminated composite structures, including those available in finite element analysis packages. However, the filament winding mosaic pattern of the composite layer could significantly affect the stress field developed due to rotational loading. This paper presents results of the finite element modelling and stress analysis of a filament wound spinning composite disk with different types of filament winding mosaic pattern. The disk has also been modelled and analysed using conventional method and differences in the predicted stress values from both techniques are demonstrated through stress distributions. As illustrated, the level of stresses in the thin filament wound composite flywheel disk could be underestimated by the structural analysis based on conventional mechanics of laminated structures.